The American Military Spouses Choir performs on 'America's Got Talent' in this image taken from video. ()

Marine wife Ashley Heaton expects she will be nervous tonight when she performs with 37 other military spouses on “America’s Got Talent,” knowing millions are watching.

“We’re not just representing our group. We represent spouses everywhere,” she said.

The American Military Spouses Choir has advanced to the semi-finals, and hopes its performance — and America’s votes — will get them through to the finals.

“America’s Got Talent” airs at 9 p.m. Eastern on NBC. Twelve acts will vie for a place in the finals.

The spouses have been in New York rehearsing for a week. “America’s Got Talent” personnel are putting together their hair and makeup and costumes, said Victor Hurtado, a former Army sergeant and co-founder and chief creative director of the Center for American Military Music Opportunities (CAMMO), which sponsors the choir. Asked about their costumes, he said, “All I can say is, it’s glorious.”

The winning act will receive $1 million. But regardless of what happens in the competition, these spouses intend to keep singing together — although many are separated by thousands of miles.

“We have an amazing relationship in our choir. The sisterhood of military spouses is amazing in and of itself,” said Laurie Massie, an alto whose husband is a Navy lieutenant commander and chaplain stationed at Marine Corps Air Station New River, N.C. “But add on the fact that we love to sing, and it makes our bond even stronger. Now we’re watching our dreams come true in front of our faces, and it makes the bond stronger. It’s indescribable. The whole atmosphere of the group is beyond words.”

Heaton, a 21-year-old alto, is the youngest spouse of the group, and said she has gotten through her nervousness in the previous performances by thinking of her husband, Marine Cpl. Joshua Heaton, who just returned in June from a seven-month deployment to Afghanistan. “I think about our service members and what they’ve been through. Compared to what they’ve done, I have nothing to be nervous about,” she said.

She’s expecting their first child in late October; several other spouses are also expectant mothers and some have had babies in the last 16 months since they started singing together. The soloist who performed Mariah Carey’s “Hero” in the Aug. 6 show had her baby a few days after that performance, said Hurtado.

There have also been permanent change of station moves and plenty of deployments. Besides family responsibilities, many of them are also juggling jobs and school, Hurtado said. The spouses are “everything from a dialysis specialist to a doctoral student, and everything in between.”

Teresa Santee, wife of an Air Force major general, said she appreciates her bosses at Alexandria City Public Schools in Virginia allowing her to take leave without pay to sing with the spouses choir.

While presently the choir is all female, they hope to add male spouses’ voices in the future, she said.

Hurtado said the choir came together within two weeks in May 2012, after musician David Foster wanted to include a choir of military wives to perform with him at the Kennedy Center in Washington, D.C. CAMMO put out a call for spouses through the active duty community, family readiness groups and elsewhere, and listened to MP3 recordings of their voices. The spouses met — and rehearsed — for the first time the day before their performance at Kennedy Center. “America’s Got Talent” producers saw their performance on YouTube and contacted them about auditioning for the show. Some 35,000 acts auditioned for the show initially.

While the spouses originally were mostly on the east coast, PCS moves have sent them farther afield — including some on the west coast, and one in England. About two dozen are stationed in the Washington, D.C., area. They practice on their own, then as many as possible get together for practices on weekends. Those who can’t make it practice by Skype.

The women interviewed said the reaction from the military community and from the public in general has been inspiring to them. “It’s moving and touching,” said Brandy Albert, whose husband is an Army sergeant. “It’s incredible to see the organization of it all, to see 38 women come together with a common goal, on a stage where so many celebrities have walked and began or continued their dreams.”

She is almost six months pregnant with their third child, and her husband, who works at the Pentagon, has so far been able to take leave to stay with their two young girls “to help make this happen,” she said.

Hurtado a former Army sergeant who has worked with Army Entertainment and the Army’s Soldier Show, said he has worked with troops for most of his career. But he and the music director and others who direct and coach the spouses have been inspired by the spouses and now have seen a different perspective.

“We realize how the troops are able to do what they have done, with the spouses like these at home.”